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• We found a novel mutation in MEGF10. • The patient had a late onset myopathy with respiratory failure. • Muscle CT showed low density in the limb and paraspinal muscles. • The biopsied muscle showed core-like structures. • Summary of the current and reported patients proved genotype-phenotype relationship. Mutations in MEGF10 are associated with early-onset myopathy, areflexia, respiratory distress, and dysphagia (EMARDD). Recently, a mild variant phenotype of EMARDD has been reported in patients with multiple minicores in the myofibers. However, some reported patients had no clear cores. We present a patient who had progressive weakness since his 30 s and then developed severe respiratory failure at the age of 66 years and found that he had a novel mutation, p.G739R, in MEGF10. He had no clear core in the biopsied muscle. We summarize the clinical and genetic characteristics of the current and reported patients with MEGF10 and statistically evaluate the genotype–phenotype correlation. Results show that patients with missense mutations in at least one allele had significantly later onset than those with biallelic truncation mutations. [ABSTRACT FROM AUTHOR]

Cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) has recently been attributed to biallelic repeat expansions in RFC1. More recently, the disease entity has expanded to atypical phenotypes, including chronic neuropathy without cerebellar ataxia or vestibular areflexia. Very recently, RFC1 expansions were found in patients with Sjögren syndrome who had neuropathy that did not respond to immunotherapy. In this study RFC1 was examined in 240 patients with acute or chronic neuropathies, including 105 with Guillain-Barré syndrome or Miller Fisher syndrome, 76 with chronic inflammatory demyelinating polyneuropathy, and 59 with other types of chronic neuropathy. Biallelic RFC1 mutations were found in three patients with immune-mediated neuropathies, including Guillain-Barré syndrome, idiopathic sensory ataxic neuropathy, or anti-myelin-associated glycoprotein (MAG) neuropathy, who responded to immunotherapies. In addition, a patient with chronic sensory autonomic neuropathy had biallelic mutations, and subclinical changes in Schwann cells on nerve biopsy. In summary, we found CANVAS-related RFC1 mutations in patients with treatable immune-mediated neuropathy or demyelinating neuropathy. [ABSTRACT FROM AUTHOR]

Cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) has recently been attributed to biallelic repeat expansions in RFC1. More recently, the disease entity has expanded to atypical phenotypes, including chronic neuropathy without cerebellar ataxia or vestibular areflexia. Very recently, RFC1 expansions were found in patients with Sjögren syndrome who had neuropathy that did not respond to immunotherapy. In this study RFC1 was examined in 240 patients with acute or chronic neuropathies, including 105 with Guillain-Barré syndrome or Miller Fisher syndrome, 76 with chronic inflammatory demyelinating polyneuropathy, and 59 with other types of chronic neuropathy. Biallelic RFC1 mutations were found in three patients with immune-mediated neuropathies, including Guillain-Barré syndrome, idiopathic sensory ataxic neuropathy, or anti-myelin-associated glycoprotein (MAG) neuropathy, who responded to immunotherapies. In addition, a patient with chronic sensory autonomic neuropathy had biallelic mutations, and subclinical changes in Schwann cells on nerve biopsy. In summary, we found CANVAS-related RFC1 mutations in patients with treatable immune-mediated neuropathy or demyelinating neuropathy. [ABSTRACT FROM AUTHOR]

Cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) has recently been attributed to biallelic repeat expansions in RFC1. More recently, the disease entity has expanded to atypical phenotypes, including chronic neuropathy without cerebellar ataxia or vestibular areflexia. Very recently, RFC1 expansions were found in patients with Sjögren syndrome who had neuropathy that did not respond to immunotherapy. In this study RFC1 was examined in 240 patients with acute or chronic neuropathies, including 105 with Guillain-Barré syndrome or Miller Fisher syndrome, 76 with chronic inflammatory demyelinating polyneuropathy, and 59 with other types of chronic neuropathy. Biallelic RFC1 mutations were found in three patients with immune-mediated neuropathies, including Guillain-Barré syndrome, idiopathic sensory ataxic neuropathy, or anti-myelin-associated glycoprotein (MAG) neuropathy, who responded to immunotherapies. In addition, a patient with chronic sensory autonomic neuropathy had biallelic mutations, and subclinical changes in Schwann cells on nerve biopsy. In summary, we found CANVAS-related RFC1 mutations in patients with treatable immune-mediated neuropathy or demyelinating neuropathy. [ABSTRACT FROM AUTHOR]

[Display omitted] Transthyretin amyloidosis is a progressive systemic disorder that is caused by the amyloid deposition of transthyretin in various organs. Stabilization of the native transthyretin is an effective strategy for the treatment of transthyretin amyloidosis. In this study we demonstrate that the clinically used uricosuric agent benziodarone is highly effective to stabilize the tetrameric structure of transthyretin. An acid-induced aggregation assay showed that benziodarone had strong inhibitory activity similar to that of tafamidis, which is currently used as a therapeutic agent for transthyretin amyloidosis. Moreover, a possible metabolite, 6-hydroxybenziodarone, retained the strong amyloid inhibitory activity of benziodarone. An ex vivo competitive binding assay using a fluorogenic probe showed that benziodarone and 6-hydroxybenziodarone were highly potent for selective binding to transthyretin in human plasma. An X-ray crystal structure analysis revealed that the halogenated hydroxyphenyl ring was located at the entrance of the thyroxine binding channel of transthyretin and that the benzofuran ring was located in the inner channel. These studies suggest that benziodarone and 6-hydroxybenziodarone would potentially be effective against transthyretin amyloidosis. [ABSTRACT FROM AUTHOR]

Background: We previously built a pollen challenge test unit (allergen challenge chamber: ACC) to collect objective data about Japanese cedar pollinosis. In this study, we investigated adequate conditions for pollen challenge using the ACC. Methods: The study consisted of two parts. The first part was conducted in November, which is not in pollen season. Subjects were exposed to Japanese cedar pollen at a concentration of 50,000 grains/m 3 in the chamber for 120 min each day over the course of three consecutive days. The second part was conducted in April, which is just after pollen season. Subjects were exposed to Japanese cedar pollen at the same concentration (50,000 grains/m 3 ) in the chamber for 90 min on a single day. Subjects recorded nasal and ocular symptoms before challenge and every 15 min after challenge initiation. The minimum cross-sectional area in the nasal cavity was measured using acoustic rhinometry before and after challenge as an indicator of nasal obstruction. Inflammatory markers in nasal lavage fluid and serum were also measured before and after challenge. Results: Nasal and ocular symptoms were significantly exacerbated after challenge on all days of the single and 3-consecutive-day challenge tests, particularly on the third day of the consecutive challenge test. Nasal and ocular symptoms were also quickly induced with challenge immediately after the end of pollen season. No significant changes in inflammatory markers were seen. Conclusions: Care is needed with regard to pollen challenge conditions in the ACC, including timing of the challenge, to induce pollinosis symptoms that accurately reflect chronic inflammation. [ABSTRACT FROM AUTHOR]